Laurie Halse Anderson was born on October 23, 1961, in Potsdam, New York, and grew up in Syracuse with her sister, Lisa. Her father, Reverend Frank A. Halse, Jr., is a Methodist minister, and her mother, Joyce Mason (Holcomb) Halse, had a management career. Anderson's parents penned poetry and encouraged her to apply her strong imagination to reading and writing: as a child she used to pretend she was a polar bear as she waded through deep snow in her neighborhood.

Anderson often composed stories on her father's typewriter and was excited when she learned to create haiku in second grade. This experience inspired her to devote herself to understanding words in order to express herself artistically as a writer. She read voraciously through her school's library collection, which she considered magical. Anderson was drawn especially to poetry, history, and geographical and cultural books. Heidi and the dictionary were two of her favorite books.

Her extensive reading piqued an interest in foreign cultures. She traveled as an American Field Service exchange student to Denmark when she was a high-school senior. Anderson's host family resided on a pig farm where she learned Danish and local and national customs. In 1981, Anderson graduated from Syracuse's Onondaga Community College with an associate's degree then moved to Washington, D.C., to study language and linguistics at Georgetown University. She married Gregory H. Anderson on June 19, 1983. One year later, she completed a bachelor's degree at Georgetown. Her husband became the chief executive officer of Anderson Financial Systems, and the couple had two daughters, Stephanie and Meredith. Anderson is a Quaker and describes herself as politically independent.

Anderson moved near to Philadelphia, Pennsylvania, and devoted herself to her family. When her daughters were older, she began writing books to submit for publication. In 1996, Anderson published two picture books, Ndito Runs (illustrated by Anita van der Merwe), about a Kenyan girl exploring her community, and Turkey Pox (illustrated by Dorothy Donohue), featuring a girl whose family celebrated Thanksgiving differently because she had chicken pox. Ndito Runs was praised by the American Booksellers Association which named it "Pick of the Lists," and that title was also selected for recommended book lists by Kansas State Librarians, the Nevada Department of Education, and the Texas Literature Review Center. It was translated into Afrikaans, Lesotho, Xhosa, and Zulu. Anderson's third picture book, No Time for Mother's Day (1999), also illustrated by Dorothy Donohue, tells about a daughter's unique gift for her mother.

Anderson wrote Speak after she awoke from a nightmare in which a teenage girl was screaming and crying. Startled by her dream, she checked to make sure her own daughters were all right then wrote a rough draft of a young adult novel that night. Having read Mary Pipher's Reviving Ophelia: Saving the Selves of Adolescent Girls (1995) and listening to her daughters' stories about high school life, Anderson was acutely aware of the crises confronting teenage girls. She realized that her narrator, Melinda, had a story she was ready to tell. Anderson had been contemplating themes that she developed in Speak, but she had not planned to write this novel. She twice revised her dream-inspired draft prior to submitting it. Speak is Anderson's first young adult novel. After Speak was published in 1999, it received starred reviews and recognition as a New York Times and Publishers Weekly bestseller, a National Book Award finalist, a Michael L. Printz Award for Excellence in YA Literature Honor Book (1999), and an American Library Association "Best Book for Young Adults." School Library Journal named Speak the Best Book of...